[Abstract] The purpose of this study is to clarify the core competency of educational and learning support practice in higher education. The methodology of scale development is applied in order to comprehend the competency required of university staff members engaged in such practice (excluding faculty members). This study consists of three surveys: (1) a bibliographic survey, wherein 298 papers were identified and 384 descriptions related to the targeted competency were extracted from them; (2) semi-structured interviews, in which 29 university staff members who were engaged in educational or learning support activities were interviewed, and a qualitative analysis of the interview records identified 1,236 items related to competency; and (3) a web-based questionnaire survey, wherein 47 questions were generated to measure competency on the basis of seven domains, 25 categories, and 177 items obtained from the bibliographic and interview surveys. The construct validity was tested by performing a factor analysis and by analyzing the relationship between the factor score, the qualification of the staff required to provide student support, and how frequently the staff members attended training seminars. These analyses resulted in five factors and 30 items as competency scales. These factor scores were found to be higher for those staff members who had the necessary qualifications or who participated in training seminars frequently. These findings lead us to conclude that these factors and items are valid measures of competency regarding educational and learning support practice. We also expect that these factors and items are usable for further staff development in universities, such as self-assessment scales in staff development programs, and as the basic concept for formulating the goals of such programs or for understanding professional practice proficiency in educational or learning support.